Method for threading a material web into a rewinder and rewinder

ABSTRACT

Rewinder and Method for threading a material web into a rewinder, in which the start of the material web is drawn off a supply roll at full width by an auxiliary device in order to improve automation possibilities. Further, provision is made for the material web to be fed to a winding position at full width and for the auxiliary device to be released from the material web in the region of the winding position.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. § 119 of German Patent Application No. 10 2004 049 720.6 filed Oct. 11, 2004, the disclosure of which is expressly incorporated by reference herein in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a method for threading a material web into a rewinder, in which the start of the material web is drawn off a supply roll at full width by means of an auxiliary device. Furthermore, the invention relates to a rewinder having an unwind station which has at least one position for a supply roll, a winding station having at least one winding position and an auxiliary device which grips a material web from the supply roll at full width in the region of the unwind station.

2. Discussion of Background Information

A method and a rewinder of this type are disclosed by EP 0 820 946 B1. In order to make it easier to thread the material web, the material web, after it has been drawn off the supply roll, is led over a cutting device which cuts a point from the material web. For this purpose, the rewinder has at least one knife which, as the material web is drawn through, can be displaced laterally transversely with respect to the direction of movement of the material web. In this way, by using the knife, it is possible to produce a cut which runs at an angle to the direction of movement of the material web. The point has the advantage that the material web can be handled more easily. However, it has a number of disadvantages. Firstly, a certain proportion of material web is lost. This is the part in which the material web is no longer present at full width after the cutting of the point. The threading operation needs a relatively great amount of time, since the material web, after reaching the winding position, has to be drawn forward until it has arrived at full width in the winding position. As a rule, this drawing forward is carried out at a speed which is lower than the winding speed. Accordingly, a relatively great amount of time is lost. It is necessary to provide either an operator or a sensor who or which determines when the material web has reached the full width. Monitoring of this type contains an additional possible error, which makes automation more difficult.

SUMMARY OF THE INVENTION

The present invention improves automation possibilities.

In a method of the type mentioned at the beginning, the instant invention provides a material web fed to a winding position at full width and an auxiliary device being released from the material web in the region of the winding position.

With this configuration, an intermediate step which has hitherto been necessary is left out completely, namely the cutting of a point before the threading of the material web into the rewinder and the severing of the point after reaching the winding position. Instead, the material web is not only gripped over its full width but led through the entire rewinder in unchanged form, that is to say at full width, until it reaches the winding position. There, it is merely necessary to separate the material web from the auxiliary device and to have the winding operation start. Therefore, neither is a relatively great proportion of the material web lost nor is any time required in order to draw the point past the winding position. Although there is a slight material-web loss, this loss is restricted to a section which is necessary in order for it to be held firmly by the auxiliary device. The auxiliary device can be controlled automatically. Since the material web is always present at its full width, sensors which determine whether the width has been reached can be dispensed with. In addition, monitoring by an operator can be ensured substantially more easily.

The material web is preferably led through a slitter, the slitter being opened before the passage of the auxiliary device. During the production of wound rolls from a parent or jumbo reel, the material web is often cut at the same time into the width subsequently required by the user. The slitter is necessary for this purpose. A large number of wound rolls are therefore obtained from a parent reel. The slitter in many cases comprises two rows of knives, which bear on the material web from mutually opposite sides. In order to permit the material web to pass through under the control of the auxiliary device, these two rows of knives now have to be moved apart sufficiently for the auxiliary device to pass through. However, this is generally possible without difficulty.

The slitter is preferably closed after the passage of the auxiliary device and produces at least one longitudinal cut in the material web before the auxiliary device reaches the winding position. This is another measure for saving time and material. As a rule, it is wished to start winding the part webs, that is to say the winding of the material web subdivided by slitting, onto a plurality of wound rolls when the part webs are present separately from one another at the winding position. If the slitting of the material web is now begun as soon as the auxiliary device has passed through, it is possible to keep the “uncut” region very short. If, for example, the slitter is closed immediately after the passage of the auxiliary device, then an uncut region of an order of magnitude of 50 cm to 1 m remains. Only this region then has to be conveyed beyond the winding position in order to have the actual winding operation begin.

The auxiliary device preferably draws the material web further after reaching the winding position until the longitudinal cut reaches the winding position. As a result, the individual wound rolls no longer stick together.

In this case, it is preferred for the material web to be wound onto the auxiliary device in the region of the winding position until the longitudinal cut reaches the winding position. It is therefore no longer necessary to displace the auxiliary device further after reaching the winding position in order to convey the longitudinal cut(s) as far as the winding position. It is simply possible to rotate the auxiliary device or a part thereof in order to wind up the material web.

Preferably, the material web is held firmly in the region of the winding position, the material web is severed between the winding position and the auxiliary device and the auxiliary device is moved to a disposal position. In the disposal position, the severed part of the material web, in particular the uncut part, is removed from the auxiliary device, for example unwound, and fed to a pulper. The auxiliary device is then available again to pick up the next material web start.

It is also advantageous if the auxiliary device is moved in a circuit from a pick-up position to the winding position and back. In this configuration, it is possible, for example, to lead the auxiliary device through the slitter on its way from the supply roll to the winding position and, on the way back, i.e. the way from the winding position to the supply roll, to lead it around the slitter. As a result, it is possible to start winding, including slitting, as soon as the auxiliary device has arrived in the winding position. Transporting the auxiliary device back then does not disrupt the further winding operation.

In a rewinder of the type mentioned at the beginning, the present invention includes an auxiliary device that can be moved from the unwind station as far as the winding station, into the region of the winding position.

It is therefore possible to grip the material web at its start at full width with the auxiliary device. Then, if the auxiliary device is led along the subsequent course of the material web through the rewinder, it draws the material web behind it at full width. It is then merely necessary to ensure that the auxiliary device comes into the region of the winding position in order that, after being severed from the auxiliary device, the material web can be wound up onto cores lying ready in the winding position.

Between the unwind station and the winding station, there is preferably arranged a slitter, the slitter having a cutting state, in which it produces at least one longitudinal cut in the material web passing through, and a passage state, in which the auxiliary device can be moved through the slitter. As a rule, the slitter has two rows of knives arranged on both sides of the material web in order to subdivide the material web into a plurality of part webs, two knives always interacting in order to produce a longitudinal cut. Therefore, in the cutting state, the knives have virtually no spacing or even overlap slightly. Then, if the auxiliary device is led through the slitter, the auxiliary device needs some space. For this purpose, the knives are moved apart accordingly. This is then the passage state. As a result of changing between the two states, it is possible to lead the material web through the entire rewinder at its full width, specifically through the slitter as well.

In this case, it is preferable for the slitter to have two crossmembers, of which at least one can be displaced relative to the other. By the displacement of the crossmembers, it is possible in a straightforward manner to create the necessary space which is needed to lead the auxiliary device with the attached material web through the slitter. The displacement of at least one crossmember is generally simpler to implement than a correspondingly large displacement of the knives on this crossmember.

The auxiliary device is preferably guided on two movement paths which are arranged transversely with respect to the direction of movement of the material web and at a predetermined distance from each other. For example, the movement paths can be formed by rails or guides. The fact that the auxiliary device is supported on two sides means that it is guided very stably. By using a support of this type, the material web can be led through the rewinder without there being any risk of creasing or tearing. The distance between the two movement paths also achieves high security against tilting.

In this case, it is particularly preferable for the movement paths to be arranged laterally outside the material web. These movement paths then do not disrupt the remaining constituent parts of the rewinder during operation. In particular, it is not necessary to take any measures in the region of the slitter in order to be able to close the slitter in spite of the presence of the movement paths. The movement paths are located laterally outside the slitter.

The movement paths of the auxiliary device are preferably led in a circuit. Therefore, the auxiliary device can be led from the unwind station to the winding station on a first section of the movement paths and led back from the winding station to the unwind station in a second section. Leading the auxiliary device back therefore does not disrupt the operation of the rewinder.

Alternatively or additionally, provision can be made for the movement paths to be designed for a bidirectional movement. In other words, the auxiliary device, if necessary, can be led back from the winding station to the unwind station on the same section of the movement paths on which it has taken the opposite route during threading. Under certain circumstances, this has the disadvantage that the slitter can start its work somewhat later, since it has to remain open until the auxiliary device has been moved back. However, it is possible to accept this disadvantage when space is restricted.

A transport device is preferably guided along at least one movement path. It is therefore not necessary for the auxiliary device itself to have a drive which moves with the auxiliary device. Instead, a stationary drive can be provided which then acts on the transport device. The transport device can be formed, for example, as a chain, belt or cable and draw the auxiliary device along the movement paths.

It is also advantageous if a crosscutter which acts on the material web between the auxiliary device and the winding position is arranged in the region of the winding position. With the aid of the crosscutter, the material web can therefore be severed between the winding position and the auxiliary device. This simplifies the threading of the material web. It is not necessary to release the material web from the auxiliary device first. Accordingly, it is not absolutely necessary to take care that the start of the material web is not damaged when it is gripped by the auxiliary device. A small section of the material web can be accepted as a loss, as long as it is the section which is needed by the auxiliary device to hold the material web.

It is also advantageous if the unwind station has a preparation position, underneath which a pulper opening is arranged, it being possible for the auxiliary device to be moved through a region between the preparation position and the pulper opening. The unwind station generally has an unwinding position in which the parent reel is located as it is unwound. In order to permit the smoothest possible change between two parent reels, at least one further space, namely a preparation position, is provided in the unwind station. In this preparation position, a new parent reel is prepared, that is to say outer layers, which may possibly be damaged, are unwound and the straightest possible leading edge of the material web is produced, which runs at an angle of about 90° with respect to the direction of movement of the material web. This operation is also designated “squaring”. Since, during this operation, some broke arises, namely the outer layers of the parent reel, it is expedient to have this broke get directly into the pulper opening. This then leads to the start of the material web hanging virtually vertically downward into the pulper opening from the preparation position. In this state, it is relatively easy to grip the material web with the auxiliary device. It is merely necessary to move the auxiliary device up to the material web from behind, so to speak, that is to say the rear side of the material web as viewed in the direction of movement. When the auxiliary device has gripped the material web there, the material web can then be transported to the winding position by means of a simple onward movement of the auxiliary device.

A crosscutter is preferably arranged in the region. This facilitates the production of a clean material web start. When the auxiliary device has gripped the material web, the crosscutter comes into action and severs the material web underneath the auxiliary device. The severed part falls into the pulper. The auxiliary device then holds the start of the material web firmly.

The crosscutter preferably has a dividing region which can be displaced in the direction of movement of the material web. In some cases, the parent or jumbo reels do not always have the same diameter. If the parent reel is always stopped in the same preparation position, then the start of the material web also hangs downward at different positions in the direction of movement. This is generally no problem for the auxiliary device, since it can be displaced in the direction of movement in any case and can therefore accommodate the small positional differences. If the slitter can likewise be displaced, then it is likewise possible to cope with these positional differences.

The auxiliary device preferably has suction openings and/or clamping means. Those are used to hold the start of the material web firmly. Suction openings hold the material web firmly with vacuum. Of course, in this case, it is necessary to ensure that air can be extracted from the auxiliary device or in any case from the suction openings. In the case of clamping means, it is merely necessary to ensure that these clamping means can grip the start of the material web and hold it firmly. Both holding devices can be controlled remotely, i.e. they can be operated from outside.

In this case it is preferred if an activation device acting on the auxiliary device is arranged in the region of the unwind station. It is then possible to activate the auxiliary device at the instant at which it is to grip the material web. If the auxiliary device holds the material web firmly with the aid of suction openings, for example, then a vacuum can be produced in the auxiliary device with the aid of the activation device. If the material web is held firmly with the aid of clamping means, then the activation device can actuate the clamping means. As a rule, it is sufficient here if the activation device acts on the auxiliary device only at the start of the firm holding action. It is therefore possible to leave the activation device to be stationary, under certain circumstances small possible movements being provided in order to take account of the different diameters of the parent reels. However, it is not necessary for the activation device to be moved from the unwind station to the winding station and back. This makes the guidance easier.

The activation device is preferably constructed as a rotational drive which can be brought into an operative connection with the auxiliary device. The rotational drive therefore rotates the auxiliary device, so that the auxiliary device winds up the start of the material web. As soon as a predetermined number of wound layers has been reached, the material web holds firmly on the auxiliary device, as long as there is a certain tension. It is then possible, for example, to switch off the vacuum on the suction openings or to reduce the force of the clamping means. The operative connection between the rotational drive and the auxiliary device can be produced via a clutch that can be engaged, so that the rotational drive does not also have to participate in the entire movement of the auxiliary device.

A rotational drive that can be brought into an operative connection with the auxiliary device is preferably arranged in the region of the winding position. This rotational drive can also be coupled to the auxiliary device, for example by means of a clutch, after the winding position has been reached. The rotational drive permits the auxiliary device to be rotated further and to wind up a region of the material web which has not been cut by the slitter. This makes it possible to draw the material web into the winding position, without further displacement of the auxiliary device, to such an extent that only already cut part webs are present at the winding position and these can be wound up to form separate wound rolls.

A splice station is preferably arranged between the unwind station and the slitter. A splice station of this type can, for example, produce what is known as a “butt splice”, as described in DE 199 23 097 A1. The splice station makes it possible to dispense with renewed insertion or threading of the material web into the rewinder when parent reels are changed. The start of a new parent reel is simply joined to the end of a virtually unwound parent reel.

The auxiliary device can preferably be moved in a space below a floor level on which the unwind station and the winding station are arranged. In other words, the movement of the auxiliary device takes place in the “basement”, while the unwind station and the winding station are arranged on the “ground floor”. This arrangement increases safety. The risk that operators who remain in the region of the unwind station and the winding station will come into contact with the auxiliary device and be injured in the process is comparatively low.

Other exemplary embodiments and advantages of the present invention may be ascertained by reviewing the present disclosure and the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is further described in the detailed description which follows, in reference to the noted plurality of drawings by way of non-limiting examples of exemplary embodiments of the present invention, in which like reference numerals represent similar parts throughout the several views of the drawings, and wherein:

FIG. 1 shows a first embodiment of a rewinder in a schematic illustration;

FIG. 2 shows a second embodiment of a rewinder in a schematic illustration;

FIG. 3 shows a detail X according to FIG. 2; and

FIG. 4 shows a detail Z according to FIG. 2.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present invention. In this regard, no attempt is made to show structural details of the present invention in more detail than is necessary for the fundamental understanding of the present invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the present invention may be embodied in practice.

FIG. 1 shows a schematic illustration of a rewinder 1 having an unwind station 2 and a winding station 3. A slitter 4 is arranged between the unwind station 2 and the winding station 3.

In the unwind station, an unwinding position 5 is provided. In the unwinding position 5 there is an unwind bearing 6, in which a spool 7 is rotatably mounted. Wound onto the spool 7 is a parent reel 8, of which a residue can still be seen in FIG. 1. A material web 9 is drawn off the parent reel 8, which can also be designated a “jumbo reel”. This material web 9 is cut into a plurality of part webs in the slitter 4 and wound up in the winding station 3 to form a plurality of wound rolls 10, of which only one can be seen in FIG. 1, since these wound rolls 10 are located one behind another in a direction at right angles to the plane of the drawing.

The unwind bearing 6 is suitable for relatively high speeds. For example, the material web 9 can be drawn off at a speed of 2000 to 3000 m/min. Of course, an identical unwind bearing 6 is arranged on the opposite side of the spool 7.

The wound rolls 10 rest on two carrier rolls 11, 12, of which at least one is driven. A loading roll 13 can be provided in order to control the winding operation. Instead of the “double carrier roll winder” illustrated, a supporting roll winder can also be provided, in which the wound rolls 10 are held centrally and rest on a supporting or contact roll.

The unwind station 2 also has a preparation position 14, in which a further spool 15 with a new parent reel 16 is kept ready. The preparation position has a preparation bearing 17, which likewise permits rotation of the spool 15 but is constructed in a less complicated manner, since the speeds of revolution needed here are far lower. The preparation bearing 17 and the unwind bearing 6 are joined to each other by a running track 18, on which the spool 15 in the preparation position 14 can roll toward the unwinding position 5 when a spool change is necessary.

The parent reel 16 is prepared in the preparation position 14. For the purpose of preparation, as a rule some layers of the material web are unwound and disposed of. This procedure is also designated “squaring”. In order to accommodate the section of the material web 9 to be disposed of, a pulper opening 19 is provided, which is arranged underneath the preparation position 14, specifically in such a way that the material web 9 hanging downward under the action of the force of gravity encounters the pulper opening 19. Since the parent reel 16 does not always have the same radius, the position of the material web 9 hanging down is displaced slightly. However, the pulper opening 19 is so large that it can intercept the material web falling down. If appropriate, a hopper 20 can also additionally be provided.

It is now occasionally necessary to lead the material web 9 from the unwind station 2 to the winding station 3. In the process, the material web 9 also has to be led through the slitter 4. This process is also designated “threading”.

For the purpose of threading, the rewinder 1 has an auxiliary device 21, which is illustrated in different positions in FIG. 1. For the purpose of distinction, the auxiliary device 21 is provided with small letters (a, b, c) in different positions.

The auxiliary device 21 is led along a movement path 22 which is illustrated as a dash-dotted line. The movement path is implemented by means of rails or guides, which are arranged on both sides of the material web 9, outside its width. A chain, a belt or a cable can also be led along the movement path 22, these devices being driven by a common drive in a manner not specifically illustrated, so that the auxiliary device 21 can be led from the unwind station 2 to the winding station 3 in an orientation at right angles to the direction of movement of the material web 9.

The auxiliary device 21 is now moved up from the left (based on the illustration of FIG. 1) to the material web 9 hanging vertically downward under the action of the force of gravity and is fixed to the material web. For example, the auxiliary device 21 can have suction openings in a manner not specifically illustrated. If a vacuum is produced at the suction openings, the auxiliary device 21 then holds the material web 9 firmly. Instead of the suction openings, clamping means which hold the material web 9 firmly can also be provided. Finally, it is also possible for the auxiliary device 21 to be rotated about an axis (at right angles to the plane of the drawing), so that it winds up the material web 9 hanging down with a few revolutions. As long as sufficient tension is maintained in the material web 9, the material web 9 holds firmly on the auxiliary device 21. For the purpose of winding, the auxiliary device 21 can be connected to a stationary rotational drive, not specifically illustrated.

As soon as the auxiliary device 21 has gripped the material web 9, a crosscutter 23 can be actuated, which severs a superfluous section 24 of the material web 9. This section 24 then likewise falls into the pulper opening 19. The crosscutter 23 can be displaced in the direction of a double arrow 25 in order to accommodate differences in the radius of the parent reel 16 which are reflected in different positions of the material web 9 hanging down. A change of this type in the position of the material web 9 is not critical for the auxiliary device 21, since it can be moved along the movement path 22 in any case.

The auxiliary device 21 is then displaced along the movement path 22 to the winding station 3 and in the process leads the material web 9 around a plurality of deflection rollers 26 as far as the winding station 3. The movement path 22 maintains a sufficient distance from the deflection rollers 26-29 so that the material web 9 which is drawn behind the auxiliary device 21 wraps around the defection rollers 26 in such a way as is subsequently necessary during operation. However, the auxiliary device 21 does not collide with the deflection rollers 26-29. At the same time as the start of the material web is being guided, the new parent reel 16 can be displaced into the unwinding position 5.

The cutting device has an upper crossmember 30 with upper knives 31 and a lower crossmember 32 with lower knives 33. The lower crossmember 32 can be displaced in the direction of a double arrow 34, so that the lower knife 33 in the cutting position illustrated dash-dotted can be displaced into a passage position illustrated by continuous lines. The slitter 4 therefore has a cutting state, in which the material web 9 can be cut into a plurality of part webs, and a passage state, in which upper knife 31 and lower knife 33 are at a distance from each other which is so large that the auxiliary device 21 can be moved through between the upper knife 31 and the lower knife 33 without difficulty.

Immediately after the passage of the auxiliary device 21, the slitter 4 is closed again, so that the longitudinal cuts begin at a relatively short distance from the auxiliary device 21. This distance can be 0.5 to 1 m.

The auxiliary device moves further until, in a position 21 c, it brings the material web into contact with a carrier roll 12. The entire process described to this point proceeds at full width, that is to say the material web 9 is gripped by the auxiliary device 21 at full width, is conveyed through the slitter 4 at full width and is placed on the carrier roll 12 at full width. There, it can be held firmly, for example by being attracted by suction.

The auxiliary device 21 c is then rotated further until the longitudinal cuts produced by the slitter 4 also arrive on the carrier roll 12. After that, a crosscutter 35 comes into action and severs the material web 9 between the auxiliary device 21 c and the carrier roll 12. As soon as the material web 9 has arrived on the carrier roll 12, it is located in what is known as the “winding position”. The crosscutter 35 can then be displaced toward the carrier roll 12 in the direction of a double arrow 36 and sever the material web 9 between the auxiliary device 21 c and the winding position, that is to say the carrier roll 12. After that, the auxiliary device 21 c can be moved into its initial position again. The crosscutter 35 is moved out of the movement path of the auxiliary device 21 c before being moved in the direction of the double arrow 36 again.

As soon as the cut material web 9 has arrived in the winding position, the winding operation can begin. Therefore, during winding, the auxiliary device 21 c can be moved back into its initial position, so that the time loss is extremely low. The initial position is located above the pulper opening 19, so that the material web residue wound up onto the auxiliary device 21 can be disposed of simply by unwinding it into the pulper opening 19.

A rotational drive which is external and not specifically illustrated can also be provided in the region of the winding position and rotates the auxiliary device 21 c until the longitudinal cuts or the longitudinal cut have/has arrived on the carrier roll 12. In this way, the need to displace the auxiliary device 21 c again in order to convey the longitudinal cut as far as the carrier roll 12 is avoided.

In addition to the time saving, the result is also a material saving, since the wastage of the material web 9 is substantially less than when a wedge or a point is used, as is generally usual in the prior art.

The auxiliary device 21 a can also be used to produce what is known as a “splice”. For this purpose, a splice device 37, which can be displaced in the direction of a double arrow 38, is arranged between the unwinding position 5 and the slitter 4. The auxiliary device 21 a is first used to bring the material web 9 unwound from the parent reel 8 into contact with the splice device 37. The splice device 37 holds the material web 9 firmly and separates it from the parent reel 8.

After that, the auxiliary device 21 can grip the material web 9 from the new parent reel 16 and likewise lead it to the splice device 37. There, the two material web ends are then joined to each other, for example as described in DE 199 23 097 A1. In this case, the auxiliary device 21 is moved both forward and rearward along the movement path 22. However, provision can also be made for the auxiliary device 21 to be moved only in one direction along the movement path 22 during this operation.

FIG. 2 shows a modified embodiment of a rewinder 1, in which identical and mutually corresponding parts are provided with the same designations. Here, the unwind station 2 has only the unwind bearing 6. When a spool change is necessary, the parent reel 8 can be removed upward, for example, in order to insert a new parent reel 16.

The configuration according to FIG. 2 differs in two substantial points from the configuration according to FIG. 1. The auxiliary device 21 (see FIG. 3) has a knife 39 which is moved together with the auxiliary device 21. When this knife 39 is intended to cut the material web 9 across, then an opposing holder 40, which remains in a fixed location in the winder 1, is moved toward the material web 9 in the direction of a double arrow 41.

Furthermore, the auxiliary device 21 has a deflection roller 42. This deflection roller 42 can have a number of tasks. Firstly, it can be used to wind up the start of the material web 9 with a few revolutions in order to hold this start firmly. However, it is also used to deflect the material web 9 when the auxiliary device 21 is in its initial position, illustrated at the bottom left in FIG. 2, in which it grips the material web 9.

In the embodiment according to FIG. 2, the movement path 22 is not led in a circuit; instead the auxiliary device 21 is moved back and forth on the same movement path 22. When, therefore, the auxiliary device 21 has transferred the material web 9 to the carrier roll 12, then the auxiliary device 21 is located above the material web 9. When the auxiliary device 21 is then moved back into its initial position, there would be the risk of the material web coming into contact with the auxiliary device 21 at other points and being damaged.

If, on the other hand, the spool 7 is inserted into the unwind bearing 6 in an orientation which is rotated through 180°, another auxiliary device 21, which is illustrated in FIG. 4, can then be used. This auxiliary device 21 also has a knife 39 which is moved together with it. When this auxiliary device 21 has transferred the material web 9 to the carrier roll 12, it is then located on the “correct” side of the material web 9.

Provision is made in this exemplary embodiment, too, for the lower knife crossmember 32 to be lowered with respect to the upper knife crossmember 30 when the auxiliary device 21 is passing through the slitter 4.

In both embodiments, provision is made for the movement path 22 to be arranged below a plane 43 in which the unwind station 2 and the winding station 3 are arranged. For example, the movement path 22 can be arranged in a basement room, while the two winding stations 2, 3 are arranged on the ground floor. This makes the provision of protective measures easier. The endangering of persons is far lower.

It is possible to deviate from the embodiments illustrated. For example, it is entirely possible to configure the movement path 22 with not just one circuit. Two or more circuits can also be provided, a corresponding number of auxiliary devices then being used, which accept the material web 9 at the transition from one circuit to another.

It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to an exemplary embodiment, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the present invention has been described herein with reference to particular means, materials and embodiments, the present invention is not intended to be limited to the particulars disclosed herein; rather, the present invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims. 

1. A method for threading a material web into a rewinder, in which the start of the material web is drawn off a supply roll at full width by means of an auxiliary device, wherein the material web is fed to a winding position at full width and the auxiliary device is released from the material web in the region of the winding position.
 2. The method as claimed in claim 1, wherein the material web is led through a slitter, the slitter being opened before the passage of the auxiliary device.
 3. The method as claimed in claim 2, wherein the slitter is closed after the passage of the auxiliary device and produces at least one longitudinal cut in the material web before the auxiliary device reaches the winding position.
 4. The method as claimed in claim 3, wherein the auxiliary device draws the material web further after reaching the winding position until the longitudinal cut reaches the winding position.
 5. The method as claimed in claim 4, wherein the material web is wound onto the auxiliary device in the region of the winding position until the longitudinal cut reaches the winding position.
 6. The method as claimed in claim 1, wherein the material web is held firmly in the region of the winding position, the material web is severed between the winding position and the auxiliary device and the auxiliary device is moved to a disposal position.
 7. The method as claimed in claim 1, wherein the auxiliary device is moved in a circuit from a pick-up position to the winding position and back.
 8. A rewinder having an unwind station which has at least one position for a supply roll, a winding station having at least one winding position and an auxiliary device which grips a material web from the supply roll at full width in the region of the unwind station, wherein the auxiliary device (21) can be moved from the unwind station (2) as far as the winding station (3), into the region of the winding position (12).
 9. The rewinder as claimed in claim 8, wherein, between the unwind station (2) and the winding station (3), there is arranged a slitter (4), the slitter (4) having a cutting state, in which it produces at least one longitudinal cut in the material web (9) passing through, and a passage state, in which the auxiliary device (21) can be moved through the slitter (4).
 10. The rewinder as claimed in claim 9, wherein the slitter (4) has two crossmembers (30, 32), of which at least one can be displaced relative to the other.
 11. The rewinder as claimed in claim 8, wherein the auxiliary device (21) is guided on two movement paths (22) which are arranged transversely with respect to the direction of movement of the material web (9) and at a predetermined distance from each other.
 12. The rewinder as claimed in claim 11, wherein the movement paths (22) are arranged laterally outside the material web.
 13. The rewinder as claimed in claim 11, wherein the movement paths (22) of the auxiliary device are led in a circuit.
 14. The rewinder as claimed in claim 11, wherein the movement paths (22) are designed for a bidirectional movement.
 15. The rewinder as claimed in claim 11, wherein a transport device is guided along at least one movement path.
 16. The rewinder as claimed in claim 8, wherein a crosscutter (35) which acts on the material web (9) between the auxiliary device (21) and the winding position (12) is arranged in the region of the winding position (12).
 17. The rewinder as claimed in claim 8, wherein the unwind station (2) has a preparation position (14), underneath which a pulper opening (19) is arranged, it being possible for the auxiliary device (21) to be moved through a region between the preparation position (14) and the pulper opening (19).
 18. The rewinder as claimed in claim 17, wherein a crosscutter (23) is arranged in the region.
 19. The rewinder as claimed in claim 18, wherein the crosscutter (23) has a dividing region which can be displaced in the direction of movement of the material web.
 20. The rewinder as claimed in claim 8, wherein the auxiliary device (21) has suction openings and/or clamping means.
 21. The rewinder as claimed in claim 8, wherein an activation device acting on the auxiliary device (21) is arranged in the region of the unwind station (2).
 22. The rewinder as claimed in claim 21, wherein the activation device is constructed as a rotational drive which can be brought into an operative connection with the auxiliary device (21).
 23. The rewinder as claimed in claim 8, wherein a rotational drive that can be brought into an operative connection with the auxiliary device (21) is arranged in the region of the winding position.
 24. The rewinder as claimed in claim 8, wherein a splice station (37) is arranged between the unwind station (2) and the slitter (4).
 25. The rewinder as claimed in claim 8, wherein the auxiliary device can be moved in a space below a floor level (43) on which the unwind station (2) and the winding station (3) are arranged. 